Mozilla researcher Andreas Gal said the project would expand the capabilities of web applications and described B2G as “a complete, standalone operating system for the open web”.

At the moment building an app for most mobile devices means making something that is specific to the operating system that runs the device. For example, iOS on an Apple mobile device and Windows Phone 7 on a Windows Phone. Web apps are a way round this problem but, at present, they have limitations.

Web apps - applications that generally run inside a browser and require internet access to function fully - are frequently less capable than native applications, which run outside of the browser and are closely linked to the underlying operating system.

The advantage of web apps is that they run in more or less the same way across different operating systems. However, their weakness is that they are less able to take advantage of specific operating system features.